//=============================================================================
// System  : MatchKit
// File    : ReflectionUtils.cs
// Author  : Fabio Bussu  (matchkit@fabiobussu.it)
// Updated : 04/16/2013
// Note    : Copyright 2013, Fabio Bussu, All rights reserved
//
// This code is published under the Microsoft Public License (Ms-PL). A copy
// of the license should be distributed with the code.  It can also be found
// at the project website: http://matchkit.codeplex.com. This notice, the
// author's name, and all copyright notices must remain intact in all
// applications, documentation, and source files.
//
// Version     Date     Who  Comments
// ============================================================================
// 1.0.0.0  04/16/2013   FB  First draft
//=============================================================================
using System;
using System.Globalization;
using System.Reflection;

namespace MatchKit.ObjectMapping
{
	static class ReflectionUtils
	{
		public static bool IsAllocable(Type type, bool alsoPrivate = true)
		{
			return !type.IsAbstract
				&& !type.IsInterface
				&& Utils.HasDefaultConstructor(type, alsoPrivate);
		}

		public static bool IsMatchableClass(Type type)
		{
			return ReflectionUtils.GetAttribute<MatchableClassAttribute>(type) != null;
		}

		public static bool IsNumber(Type type)
		{
			return type == typeof(byte)
				|| type == typeof(sbyte)
				|| type == typeof(short)
				|| type == typeof(ushort)
				|| type == typeof(int)
				|| type == typeof(uint)
				|| type == typeof(long)
				|| type == typeof(ulong)
				|| type == typeof(decimal)
				|| type == typeof(float)
				|| type == typeof(double);
		}

		public static object CastNumberTo(object number, Type type)
		{
			var c = (IConvertible)number;
			if (type == typeof(int)) return c.ToInt32(CultureInfo.InvariantCulture);
			if (type == typeof(byte)) return c.ToByte(CultureInfo.InvariantCulture);
			if (type == typeof(long)) return c.ToInt64(CultureInfo.InvariantCulture);
			if (type == typeof(short)) return c.ToInt16(CultureInfo.InvariantCulture);
			if (type == typeof(float)) return c.ToSingle(CultureInfo.InvariantCulture);
			if (type == typeof(decimal)) return c.ToDecimal(CultureInfo.InvariantCulture);
			if (type == typeof(double)) return c.ToDouble(CultureInfo.InvariantCulture);
			if (type == typeof(uint)) return c.ToUInt32(CultureInfo.InvariantCulture);
			if (type == typeof(ulong)) return c.ToUInt64(CultureInfo.InvariantCulture);
			if (type == typeof(sbyte)) return c.ToSByte(CultureInfo.InvariantCulture);
			if (type == typeof(ushort)) return c.ToUInt16(CultureInfo.InvariantCulture);

			throw new MatchKitMappingException(-1, "Internal error. Invalid number [" 
				+ number.ToString() + "] cast to [" + type.FullName + "]");
		}

		public static T GetAttribute<T>(
			#if EM
			this 
			#endif
			MemberInfo member)
			where T: Attribute
		{
			var k = member.GetCustomAttributes(typeof(T), true);
			if (k != null && k.Length != 0)
				return (T)k[0];
			else
				return null;
		}
	}
}
